Speedometer



BEST AVAILABLE COP J. D. ROBERTSON.

SPEEDOM ETER.

APPLICATION FILED JAN. 12. 918. 1,386,953. Patented Au 9, 1921.

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APPLICATION men IAN. 1.2, 191.8.

1,886,953, Patented Aug. 9, 1921.

15 SHEETS-SHEET BEST AVA? BLE COP J. D. ROBERTSON.

SPEEDOMETER.

APPLICATION man JAN. 12. 191.8. 1,386,953. at ted Aug. 9, 1921.

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- Inventor.- John 13.120 hes-wits o :1,

BEST AVA'KLAESLE QOP" J. D. ROBERTSON.

SPEEDOMETER.

APPLICATION FILED JAN. 12, 1918.

1,386,953. v PatentedAug. 9,1921.

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Iii/Denier.- JohnlhRoberii n,

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BEST AVAILABLE COP.

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SPEEDOMETER.

APPLICATION FILED JAN. 12, 1.91.8,

1,386,953. PatentedAug. 9, 1921.

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BEST AVAHABLE CG?" 1. D. ROBERTSON.

SPEEDOMETER.

APPLICATION FILED m4. l2, I918.

1,386,953. Patented Aug. 9, 1921.

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by W M fla s.

BEST AVi XiU-XBLE CO .I. D. ROBERTSON.

SPEEDOMETER.

APPLICATION FILED JAN. 12. 1913.

1,886,953. Patented Aug. 9, 1921.

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BEST AVAELABLE COP J. D. ROBERTSON.

SPEEDOMETER.

APPLICATION FILED JAN. 12. 1918.

1,386,953. Patented Aug. 9, 1921.

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SPEEDOMETER; APPKICATION FILED Mk. 2. 1918..

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SPEEDOMETER.

APPLICATION man JAN.12, 1.914;.

1,886,953, Patented Aug. 9, 1921.

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.IW/venior John D.Bobei"i'son,

BEST AVAHABLE CUP J. D. ROBERTSON SPEEDOMETER.

APPLICATION mzo JAN. 12. 1am.

Patented Aug. 9, 1921.

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APPLICATION FILED JAN. 12, 1918. 1,386,953. Patented Aug. 9,1921.

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ROBERTSON, E raumon, MASSACHUSETTS.

Be it known that I, J oniv, D. ,RonER'rsoN, a citizen of the United States, and agresident of Taunton, county of- Bristol, and Gommonwealth of Massachusetts, have'inventedan Improvement in-Speedometers, of; which ,the following description, connection ,with the accompanying:drawings, is a'specification, like characters .on thezdrawings representing like parts;

This invention relates to an instrument for ascertaining characteristics of motion of a moving body'whichcarr ies the instrument. The moving body may be anyiair or water craft, Or any vehicle traveling onland; My invention is :more particularly concerned with an instrumentgfor continuously furnishing direct readings of acceleration and retardation, fore andaft-velocity,- lateral velocitydue toside drift, true velocity. and direction, and the angle between such true direction and a fixed dine which may the fore and aft center line of the moving body, as well as for furnishing readingsfshowing the angles of fore and aft-,and' lateral inclination o f the body; Y

Briefly stated,-the instrument may he said to comprise a lateral acceleration and retardation responsive and integrating device to give sidewise speed, alongitudinal acceleration and retardation responsive and integrating device. to give fore and aft speed, a device to add these two components of speed to show the true speed and the true direction of motion relative to the longitudinal center line of the craft, a true speed integrating device to givethe true distance t'raveled, a centrifugal force responsive correcting device similar to the acceleration responsive devices, but maintained atright angles to the line of motion, a device to resolve the entrit'ugal force into components laterally and longitudinally of the craft, and means for applying, these components to the lateral and longitudinal acceleration responsive devices as corrections.

It should here be noted that the instrument neglects .diiierences in elevation of the moving body, but gives the horizontal component only of motion, speed and distance, (which herein is spoken of as true speed, distance, and direction), as it is this which is needed for mapping and charting. In other Words, the instrumcntignores up and down sREEnoMETER H specifica tipii'of Letters Patent. Patented Aug. 9 1921 .,Api)1.ication'fi1ed January 12, 1918. I I

Serial No. 211,500.

movements of the moving body, such for ex ample; as ,the ascending; and descending -movements ,of; an aircraft or submersible craft,.or the efi'ectsof waveaction on the surface of the. water, or the hills and valleys [of the earth. :In 'short,the.instrument gives what is needed, viz: the'distance on the map.

My invention will be best understood by reference to the following description,when taken in connection I'w-ith-theaccompanying drawings of Bone illustrative embodiment the'reofiwhile its scope will be'moreparticularly pointed out in the appended claims.

For convenience in considering the drawings, I have marked each viewwith a symbol indicating direction, ::and-

these symbols, the letters F-A, LR- and: T 13 indicate, respectively, fore and aft, right and left and top; andzbottom.4.52am? In the drawings: Figure 1 is'ga plan of an -instrument'em 'bodying my'invention;: I I

Fig. 2 is a rear elevation of the same; Fig. is a detail'i'elevation of the fore and aft inclination indicating device, as viewed from the right-hand side of Figs. 1 and 2.; Fig. 4 is a-detail, sectional view on line 44'of Fig.1;- w 4 Fig. 5 is av detail, sectional view on -line 55 of Fig. 1;

Fig. 6 is a sectional-view on line 6-6 of 1, looking forward, Fig. 7 is a detail elevation of the fore and aft acceleration and retardation indicator, as viewed from the right-hand side of Fig. 6; Fig. Sis a sectionalview on line 8-8 of Fig. 1, looking toward the right,

Fig. 9 is a detail elevation of the lateral acceleration and retardation indicator, as viewed from the left-hand side of Fig. 8;

' Fig. 10 is a plan section on line lO- l0 of Fig. 6;

Fig. 3.1 is a detail, sectional view on line 111l'of Fig. 10, showing the fore and aft acceleration and retardation responsive means comprising a pendulum;

Fig. 12 is a detail, sectional view on line 12-12 of Fig.;11;- i

Fig. 13 is a plan section on line 13-43 of Fig. 6;

Fig. 14: is a detail, sectional view on line 14-44 of Fig. 13, showing. the lateral acceleration and retardation responsive means the right-hand side of Fig. 19'; Fig."2l is a detail, sectional -21 21 ofFig. 19;

comprising a pendulum, andshowing also the correcting devices for the same;

Fig. is a plan section on line l5l5 of Fig. 6;

Fig. 16 is a detail, sectional view on line 16-16 of Fig. 15, showing the centrifugal "rorce responsive means comprising a pendulum;

Fig. 17 is a'detail, sectional view on line l7l7 of Fig. 16;

Fig. 18 is a plan section on line 18-18 of Fig. 6;

Fig. 19 is a detail plain (in an enlarged scale of a portion of the planetary gear set;

Fig. 20 is a detail elevation viewed from view on line Fig. 22 is a detail planon an enlarged-scale of the differential mechanism which is associated with the'fore and aft acceleration and retardation responsive means, and which forms a part of the integrating means; Fig. 23 is a detail,'sectional view on line 23-23 of Fig. 22;

Fig. 24 is a detail, sectional view on line 24 24 of Fig. 22;

Fig. 25 is a detail, sectional view on line 2525-of Fig. 22;

Fig. 26 is a detail, sectional view on line 26-26 of Fi 24, illustrating the differential gearing;

27 is an elevation of the differential gearing, viewed from the left-hand side of Fig;'26; i

Fig. 28 is an end elevation of the differential gearing, viewed from the right-hand side of Fig. 26;

Fig. 29 is a detail plan, on an enlarged scale, of the differential mechanism which is associated with the lateral acceleration and retardation responsive means, and Whirl forms a part of the integrating means;

Fig. 30 is a sectional view on line 30-30 if Fig. 29;

Fig.3l is a sectional view on line 3 of Fig. 29;

Fig. 32 is a sectional view on line 32-32 of Fig. 29;

Fig. 33 is a sectional view on line 33-33 of Fig. 31, looking toward the left, showing the differential gearing;

Fig. 34 is an elevation of the dill'erenlial gearing, viewed from the left-hand side of Fig. 33;

Fig. 35 is an elevation of the differential gearing, viewed from the right-hand side oi? Fig. 33;

Fig. 36 is a plan of a portion of the mechanism which adds thetwo components of speed to show the true speed, and which integrates the true speed to give the true distance traveled;

' Fig.- 37 is a rear elevation of the parts shown in F ig. '36;

BESTAVAiL-ac E COED.

mechanism which connects the lateral acceleration and retardation responsive device with the true speed integrating device;

' Fig. 43 is a skeletonized, perspective view of a portion of the correcting mechanism which acts on the lateral and fore and aft acceleration-and retardation responsive devices;

' Fig. 44 is a'skeletonized plan of a portion of the true speed, true distance and true direction, integrating mechanisn, showing the same in one possible position in which the moving body is traveling forward and drift ing sidewise;

F 45 is a skeletonized plan of a portion of the mechanism which connects the integrating mechanism shown in Fig. 44 with the correcting devices for the fore and aft and lateral acceleration and retardation responsive devices;

Fig. 46 is a slteletonized, perspective diagram of the electrical system of the instrument; Fig. 47 is a detail, sectional view, on an enlarged scale, on line L74:7 of Fig. 6;

Fig. L8 is an elevation, partly in vertical section, of the parts shown in Fig. l7;

Fig. 49 is a rear elevation, partly in vertical section, of a portion of the mechanism which connects the lateral acceleration and retardation responsive devices with the true speed and true distance integrating devices;

Fig. 50 is a detail elevation, partly in vertical section, of some of the parts shown in Fig. 49, as viewed from the right-hand side thereof;

Fig. 51 is a detail elevation. partly in vertical section, of a portion of the mechanism which connects the fore and aft acceleration and retardation responsive device with the true speed and true distance integrating de vices;

Fig. 52 is a detail elevation of some of the parts shown in Fig. 51, as viewed from the left-hand side thereof;

Fig. 53 is a detail plan view of a modification of the driving mechanism, connecting one of the acceleration and retardation responsive devices with the true speed and true distance integrating devices, and illustrating h'c lz'aation indicating 1 57316011218, Fig s.

aineans to :provide energy from anaoutside source to actuate-the. devices driven. by. the *diiierjential mechanism, instead of having the differential mechanism itself furnish: the

3 driving energy;

wofFig; (53.; and

oa-Figfv i813, sectional view on line of Eigs53'. 1- 11 11 11) 1 1% m i iire) ,Referringznoiwto the drawings, and to the embodiment of invention. :whiehz is -illustrated therein, and first; :rnore particularly. :to Figs. l'toj4s, inclusive, I havelshow n aispeedometer-having a mounting comprisa-;base or support 61, providedwith-a panwbif'arms orI standardsz62, 'OIlMhiCh a ring-eats .mounte'd zto turn about -a hor1zontal axis ct-a,- which :may bef'a-at right. angles .t'othe fore and :aft centerzil-ine :"Of the-craft. .:T.his ring,-r-initurn, carries a :cas1ng6t,3 which is pivoted to said' .rin'gzto swing: about. a hori'zontal'raxisb'Tb, which .-may be parallel or coincident with-the fore *zand aft-center'line Tot the craft. Thecasing 64L maybe; provided with alcover 65, having a iglazilng r66,zthrough which the trne'speed, true distance I and :true direction integration devices may he'ziviewied. -Thef eenterizo'f gravity: of the :mass of the caisingzfigand .the mechanism which itcontains is below -thevaXes1a-t-a' and and hence the eas- 1 ing :te-ndsnto remain :horizontal, despite any :inclinationrof the: craft on which 'a-it-"lis mounted, when the craftc is at' rest-or travelingla't" a-TunifOi-m" speedfi. W hen the craft is being accelerated =or "retarded, the swinging-tendency ofathe whole-' ins trument-as a pendulum on its mountingeis overcome by the movement of the acceleration and i re- ;ta'r'dation carriages hereinafter described.

Swinging tendencies of thewhole instrument as apendulum' due to centrifugal force are overcome by the movement of the centrifugal force correcting carriage hereinafter described. These balancing actions, however,

.areassisted byagyroscope, as will presently QIf desire'd; the instrument 1 be pro- .vided with suitable means for indicating the lateral and fore and aft-inclinations of thecraft, and in the presentzexample, I have shown twofsets .of inclination indicating devices,- ,:wh ich1;l will nowv';;describe.-- Secured to .on'e-of-thearm's 62-Iis-a fixed-hand or pointer 67, coeperating'awith a suitably graduated scale 68, .whic-h may be a ring br se'ctdrhsecuredto the gimbal' ring 63, as

best shown in Fig. 3. The aiis of the scale 681lS'5'QOlIlCld8IltWith; the axis 'a/-a, and lhenceeany i(!h&11ge;0f .Ore and aft inclina- QEST AVA'iLdBLE 6GP".

tion of the craft will-cause the hand or pointer 67- to move withireferenceto the scale, andlewill indicate :in degrees or other -.suitable% unitsthe :amount of inclination.

;-,The lateral inclination indicating device-- 7 comprises a similar. hand for pointer 69 and 1 graduated scale .70, whose axis is coincident with the axis Z)b the hand or pointer being secured to the glmbal ring, and the scale to the instrument c'asing. Thus "it"is evident.

that any lateral inclination of the craft will be shown eby. corresponding movement of the :handaor pointer. 69-over the scale 70, thusenabling the'amount or. lateral inclina- -'tion :to be read in:degrees or other units.

I I .l;;-As-=a means *for aiding? the. action of gravity in keeping the instrument level 'or 'fhor1zontal-,-'as well as to provide'agsource of- -;power for icertain fdevices' hereinafter described, I have;provided;a:- gyroscope linechanismcomprising :a: motor 171, which may be =..of any-suitable type, either electrical or otherwise, having a' shaft.72, which through suitable means, herein abevel pinion 73 and bevel gear'ft, drives a vertical shaft? 5, whose axis' .c'(:. is thesameas that ofrthe entire -instrument,'.=:and.- passes through the point .of intersection oflthe axes u -aizand b b,

herein springs '83, the latter in turn beingsecured to upper and lower'collars S4 and 385 'Inounted on -shaft 79; 'The upper col- .lar is mounted-in fixed position, while tho lower collar 'isam'ounted to slide vertically on the shaft, and may operate through: any appropriate inean's to control-the speed of (the -motor 71: In the present instance, I :have shown'for-this purpose carried by the .vertically sliding collar abrake disk'86 coiiperating with a brake shoe 87, which ma be adjustably mounted, thereby to permit the action of the governor to bevaried within reasonable limits. In thepresent example, I have provided for this purpose a shoe 87 and is-fulcrumed on a pivot 89. An adjusting screw QOfthreaded into the casing 64: is suitably connected to the bell crank lever to adjustrthe latter, as. for example, by providing saidxscrew with an annular groove bell 'cranklever 88 which. carries the brake 61 to receive one arm of the lever. A look nut 92 may be provided to secure the adjust ing screw in the desired position of adjustment. The governor shaft 79 may be driven by any suitable means, such, for example, as a gear 93 secured to the shaft and meshing with a gear 94 secured to the governor shaft 79.

F are and aft responsz'oe means, (Figs. 10, 11 and 12.)

I have herein provided means to indicate the velocity by utilizing the variations of inertia forces of a mass in accordance with the variations in the velocity of the craft or vehicle which carries the instrument. This mass may take various forms, but in the present example I have shown a pendulum '95, which is mounted to swing freely in a herein formed on yokes 99 suitably secured to the sides of the pendulum, said pivots resting in grooves 100 on a suitable support. In. the present example, such support is in the form of a pair offore and aft bars 101, the latter being supported at their ends on and rigidly secured to transverse bars 102, forming a part of the frame-work of the instrument. The latter bars may be suitably supported, as by means of lugs or brackets 103 projecting inwardly from the casing- 04, as best shown in Fig. 10. As a means for preventing upward displacement of the pendulum. I have herein provided the yokes 99 with laterally projecting lugs 10 1: which extend beneath the supporting bars 101, as best shown in Fig. 12. Suffic-ient clearance is provided to allow the pendulum to swing freely while still restricting its upward movement.

The arm of the pendulum 95 is extended to a considerable width in the plane of its oscillation, and intermediate its points of support it has a straight edge or surface 105, which is horizontal when the pendulum is in equilibrium. which condition obtains when the craft or vehicle is at rest or traveling at a uniform speed.

Now, it must be evident that the described pendulum is responsive to fore-and-aft acceleration and retardation, so that on the one hand when the craft or vehicle starts in a forward direction from a state of rest or in already in motion, and its speed is accelerated, the pendulum will tend to lagbe- BEST AVAiLABLE COP".

include an electric circuit of which the pendulum constitutes the making and breaking device, the pendulum for this purpose being herein provided with a pair of suitable contacts 106 which cooperate with and are adapted to make and break contact with a pair of stationary contacts 107, the latter being herein mounted on adjusting screws 108 and supported on the bars 101, from which said contacts are insulated by appropriate insulating means. herein in the form of a pair of insulating blocks 109. Because of the gimbal mounting of the instrument casing, equal gaps are normally maintained between the pairs of contacts 106 and 107 when the pendulum 95 is in equilibrium.

Connected with the stationary contacts 107 are two conducting wires 110, which may lead to any suitable means adapted to receive the electrical impulse and to transmit the same to the integrating device. present example, these wires are connected to two solenoids 111, best shown in Figs. .17 and 18. These solenoids may be and are herein co-axially alined and are inclosed in suitable casings 112, which are mounted on supporting bars 113 and 114;, the latter in turn being secured to the bars 102. The solenoids 111 are herein provided with a common core 115, which may be mounted to slide in suitable non-magnetic tubular guides 116 within the respective solenoids, as best .shown in Figs. 47 and 418. It must now be evident that when the pendulum swings in one direction, the circuit will be completed to one solenoid, thereby to energize the latter and to move the core in one direction, while on the other hand when the pendulum swings in the opposite direction, the other solenoid will be energized and the core moved in the opposite direction.

The core 115 may impart its motion through any suitable mechanism. In the present example, I have shown secured to the core a rack 1.17 meshing with a pinion 118 and adapted to'rotate the latter in one direction or the other, as the case may be, according to which of the solenoids 111 is energized. The core 115 may be held against turning movement in any appropriate manner, as by extending the rack 117 This tendency may be utilized- In the having its upper and lower ends mounted in suitable bearings 122 and-123 in the bars 113 and 114 respectively, as best shown in Fig. 48.

Also secured to the shaft 121 the;,.latter. meshing with 'an intermediate, gean125best shown-in Fig. 6. This gear 18' herein mounted to turn on a stud 126 on asupperting'. bar 127,,ibe st shown. in ,Figs, 6,

8 and 10. having its ends secured to the bars 102 hereinbcfore described. I r

T he intermediate gear 125 in turnmeshes with a rack 128, best shown in Fig. 22, forming apart ofacarriage shown in detail in Figsg22 to 25 inclusive and having a frame 129 to which saidrack is se-= cured. 'T his frame is herein mounted for fore-and-aft movement and to that end is provided with' a plurality of anti-friction rollers including roller 130 on'ojne side of the carriage and two pairsof rollers 131 and 132 on the other side. Preferably these rollers are so placed as to form a three-point support for the carriage, as best shown in Fig. 10. The roller 130 is arranged to travel on a guide which may be and herein is formed as a part of the bar 114 hereinbefore described, while the rollers 131and 1-32 are mounted. to travel ona guide134gbest1 shown in Fig. 1(),l1aving.its ends secured to the bars 102 hereinbefore described; The carriage frame is moved back and forth on these supporting bars orguides under the influence of one solenoid or the other consequent on the closing of one or the other of the two electric circuits by the oscillation of the pendulum in one direction or the other. If desired, an additional anti-fricti n guide roller 135, mounted on the rack 128 (see Fig. 22). may be arranged to bear against the under side of the bar 127. as best shown in Fig. 6. thereby to prevent the carriage from lifting from its lower guides 133 andi It must now be evident that the carriage moves to and :fro under the intermittent impulses imparted to it through the swinging motion of the pendulum. It mustalso be evident that the carriage should move with each impulse a distance proportional to the acceleration. or retardation which caused the impulse and that when thecarriage reaches the proper point the pendulum should be restored to equilibrium thereby to break the previouslycompleted circuit. To these ends. I may provide any suitable means carried by the carriage 1 as, for example, a spring 136, best shown in Figs. 10- and 11, secured to an arm 137 on the carriage frame 129 and resting 'on-t'he upper straight edgeof-the pendulum 95. lVhen the latter is QEST AVAlLABLE COP;

in equilibrium, asshown in Fig. 11, the free. end-10f the spring] 136 1 rests centrally upon the pendulunr in line with its fulcrum. Nhen. ho\vever,the carriage which carries the spring moves ,ingone direction or the other under the, impulse i which is. imparted it y h ,o 'etion of he Pendu t e spring .mQVQC:1 t-'flO11T central position in onedirection orz the otherijas the case may be, n 'n mesa'rni 5105,] When this occurs,- the ser es?1 et ml ia r s fit fie e qe e f r er r eafi -i yi, .i-i i eeee ee the fnlcrum=' and, th s force is: sufficient to.. Restore the penduliini to equilibrium thus breaking the circuit..and. -l ea v in1the carriage in. the

pa si 0' h sk; i fl= shi T e mpulse whichpit received It: should here be noted that the springmfi, in its practical sithe -eiiuiva-lent of 3a;wei ht.

cifec x As 91 ndicatinglthe ore-and. acceleral'si on' an tardatioirpllhave herein provided an acceleration-rand :retardationim: is m e fflpris 'ee ep i 138; -e t shcvn: bell es a fie ie i ie wriage Valid cooperating it a italblygradu'atedscale 139,.thg. glatterlin gthe. present imple. being] in. the... z i o f a; .window. ,mounted in one side 0'15. the casing.-

and .provided; suitable graduations aeonventionallyp shown in-v Fim ia,

Kssocia d with the} carr age frame 129 1nd: f l-mi itia izi r w'fl i rr ae flewd t.

ferent 1 7 differen-l.

an" as. Wl we by thecar lagefrapelll iePmfertblyi n t da h et g I i I capable of mov ng, a. verticalidirection. To j nd the me frames are herein connected iby 141, best shown in e i-i 22;.w1: 23:,- rirete ly connectedm t opposite ends to therespective In the present example this-link, 4 as best shown in Figs 22, is: i n the form of the letter H.

Suitably. mounted on the differential frame 140 are two friction rollers 142; and 143, best shown in Figsii2 to25 inclusive secured to shafts 144 and 145 respectively, the latter being journaled.. in su itable bearings in .the differential frame 140-. These friction-rollers rest upon andare driven by agfriction disk 146 which maybe driven by anysuitable ,source of poweizgbutin the present example as best shown inFig. 6, is secured to and driven by'the gyroscope-flywheel 7 The frictioinrollers142 and 143 are preferably of equal diameter and should all times contact with ;the friction disk 146 on that diameter o-f,the latter which is parallel with the motion 0f;the.carriage; The link 141 permits :the friction yrollers always to maintain equal driving contact with the disk 146 regardless of any possible-inaccuracies in the carriage guiding means rand in'the disk itself." The use of the link; also enables the weight of the difi'erential frame and the mamas;

ftss 

